ALABAMA PORT -- Barbara Lilley says the pain in her lower back is so great at times that she cannot walk.

Co-owner of a struggling convenience store in southern Mobile County, Lilley believes that months of lifting boxes threw her back out of whack about a year ago.

But the physicians she saw said that before they'll know exactly what's wrong, the 43-year-old needs to have a picture taken of her spine with a magnet ic resonance imaging (MRI) unit, a sophisticated machine that uses huge magnets to allow doctors to see deep inside the body.

Because Lilley has no health insurance, and doesn't qualify for the federal Medicaid program, she has to pay cash for the procedure or for any other type of health care.

"First, they told me it would cost $1,200 for the MRI," she said recently as she sat behind the counter at Lilley's Store on Alabama 188. "Then, when I got there to have it done, they said it would be $2,400. I told them there's no way I could come up with that amount of money."

Meanwhile, her general practice doctor in Bayou La Batre can prescribe only daily doses of Celebrex, a pain and anti-inflammatory medication that some studies have linked to harmful side effects over prolonged use.

What's happened to Barbara Lilley is a snapshot of the way health care works -- or doesn't work -- for an estimated 65,000 people in Mobile County who don't have insurance.

The county health department and a network of clinics, most of them federally funded, will charge uninsured patients a nominal fee based on their incomes. Lilley was seen by Dr. Regina Benjamin in Bayou La Batre, one of the few private physicians who concentrate on helping low-income patients.

But these clinics can only provide basic, primary health care such as prescribing medication, treating pneumonia or similar conditions. If patients face a true emergency, such as a heart attack, by law the hospital has to accept them.

If uninsured people such as Lilley need non-emergency but complex or invasive procedures such as an MRI or back surgery, chances are they're out of luck in Mobile, even though the city is home to 10 MRI units -- almost as many as Birmingham -- and more than 50 orthopedic surgeons.

"I never thought something like this would happen to me," said Lilley. "I'm just 43 years old, and other than my back, I'm very healthy."

"The problem is, there are way too many people here like Barbara Lilley," Benjamin said. Most of them, she said, have jobs, but can't pay for health insurance, which can run $300 to $600 a month for a family.

According to the Consumer Health Education Council, a group that advocates better access to medical care for uninsured people, more than 80 percent of the uninsured in this country are part of families headed by workers who are not offered insurance at work or who decline the coverage that's offered them.

If Lilley could afford insurance, she still may not be able to find it: many companies, including Blue Cross Blue Shield of Alabama, will not cover many pre-existing conditions. Lilley also is a smoker, which would drive up her rates.

Medicaid, the health insurance program for the poorest of the poor, doesn't help most working adults. Lilley and her husband have enough income that she doesn't qualify. To be covered by even limited Medicaid programs in Alabama, one of the lowest-paying states in the country, a couple can earn no more than about $15,000 a year -- roughly the federal poverty level.

The plight of the uninsured has drained resources from the safety net hospitals that have served as the fallbacks for care for many low-income patients. Even the University of South Alabama's hospitals, which care for three-fourths of the uninsured hospital patients in Mobile, have tightened up on their generosity and charge fees up front for some non-emergencies.

Lilley's unsuccessful MRI appointment was with a USA doctor. USA's Radiology Department told the Mobile Register that the standard price for one MRI of the lower back is $938 for the scan and $288 for the doctor to read it.

Benjamin later managed to get Lilley an appointment with an orthopedic surgeon in a private practice, Lilley said. "But the doctor wanted $400 up front before he would even talk to me," she said.

Her best hope now is that Benjamin will be able to lay her hands on an older MRI unit that HealthSouth Inc., based in Birmingham, has promised to donate for a reasonable fee, and to find a building large enough to house it. That could take months. Even if she gets an MRI scan, Lilley believes she would still need surgery, which could cost more than $40,000.

Meanwhile, Lilley continues to limp around her store. "I'm here from 6 in the morning to 8 or 9 at night, every day," she said.